[Scope map] Cope with pattern binding accessor/initializer children in any order.

Semantic analysis produces implicit accessors that can show up before initializers (e.g., for initializers), and it’s reasonable for ill-formed code to do this as well, so be more tolerant of ordering issues here.

Author: DougGregor

lib/AST/ASTScope.cpp

@@ -235,18 +235,35 @@ void ASTScope::expand() const {
       patternBinding.decl->getPatternList()[patternBinding.entry];
 
     // Create a child for the initializer, if present.
+    ASTScope *initChild = nullptr;
     if (patternEntry.getInit() &&
-        patternEntry.getInit()->getSourceRange().isValid())
-      addChild(new (ctx) ASTScope(ASTScopeKind::PatternInitializer, this,
-                                  patternBinding.decl, patternBinding.entry));
+        patternEntry.getInit()->getSourceRange().isValid()) {
+      initChild = new (ctx) ASTScope(ASTScopeKind::PatternInitializer, this,
+                                     patternBinding.decl, patternBinding.entry);
+    }
 
     // Create children for the accessors of any variables in the pattern that
     // have them.
     patternEntry.getPattern()->forEachVariable([&](VarDecl *var) {
-      if (hasAccessors(var))
+      if (hasAccessors(var)) {
+        // If there is an initializer child that precedes this node (the
+        // normal case), add teh initializer child first.
+        if (initChild &&
+            ctx.SourceMgr.isBeforeInBuffer(
+              patternBinding.decl->getInit(patternBinding.entry)->getEndLoc(),
+                                 var->getBracesRange().Start)) {
+          addChild(initChild);
+          initChild = nullptr;
+        }
+
         addChild(new (ctx) ASTScope(this, var));
+      }
     });
 
+    // If an initializer child remains, add it now.
+    if (initChild)
+      addChild(initChild);
+
     // If the pattern binding is in a local context, we nest the remaining
     // pattern bindings.
     if (patternBinding.decl->getDeclContext()->isLocalContext()) {

lib/AST/Decl.cpp

@@ -919,15 +919,23 @@ VarDecl *PatternBindingEntry::getAnchoringVarDecl() const {
 }
 
 SourceRange PatternBindingEntry::getSourceRange() const {
+  ASTContext *ctx = nullptr;
+
   SourceLoc endLoc;
   getPattern()->forEachVariable([&](VarDecl *var) {
     auto accessorsEndLoc = var->getBracesRange().End;
-    if (accessorsEndLoc.isValid()) endLoc = accessorsEndLoc;
+    if (accessorsEndLoc.isValid()) {
+      endLoc = accessorsEndLoc;
+      if (!ctx) ctx = &var->getASTContext();
+    }
   });
 
   // Check the initializer.
-  if (endLoc.isInvalid())
-    endLoc = getOrigInitRange().End;
+  SourceLoc initEndLoc = getOrigInitRange().End;
+  if (initEndLoc.isValid() &&
+      (endLoc.isInvalid() ||
+       (ctx && ctx->SourceMgr.isBeforeInBuffer(endLoc, initEndLoc))))
+    endLoc = initEndLoc;
 
   // Check the pattern.
   if (endLoc.isInvalid())

test/NameBinding/scope_map_lookup.swift

@@ -31,3 +31,12 @@ extension P2 {
     return self
   }
 }
+
+// Lazy properties
+class LazyProperties {
+  init() {
+    lazy var localvar = 42  // expected-error {{lazy is only valid for members of a struct or class}} {{5-10=}}
+    localvar += 1
+    _ = localvar
+  }
+}